Cannot set Supervisor/BIOS passwords, cannot change BIOS options

First, let me just say - if you're using HDD passwords without a valid security risk, you deserve all the frustration you cause when you forget the **bleep** thing, as well as the frustration of the poor bugger trying to fix it.

Confirming drive is frozen by entering BIOS and looking at settings

Yep, drive is frozen.

If I restart the PC and re-enter the BIOS it gives me the option to set a HDD password:

The PC will accept the new HDD password settings, and will accept the password at boot.

However because the HDD was /already/ frozen, it's not allowing access to the drive.

I can't do *anything* to recover the HDD until I can boot the PC from USB - but I don't have that option either:

Can someone *please* tell me how I can enable these settings?

I have read that you need to set a Supervisor password before you can alter these settings (which sounds a little odd, but after 2 days of InsydeH20 nothing would surprise me... worst. BIOS. ever.) - can this be confirmed? And if so, then how do I go about setting a Supervisor password when I don't have an option to??